Dantrolene e células-tronco mesenquimais promovem melhora funcional em ratos Wistar com trauma espinhal agudo / Dantrolene and mesenchymal stem cells promote functional improvement in Wistar rats with spinal cord injury

Objetivou-se avaliar o efeito do dantrolene (DAN) e das células-tronco mesenquimais (CTM) no trauma espinhal agudo (TEA). Sessenta ratos Wistar foram divididos nos grupos CTM, DAN + CTM, DAN, trauma e placebo (TP) e sem trauma e placebo (STP). Realizou-se laminectomia de T12 em todos os grupos, seguida de TEA contusivo ∕ compressivo, com exceção do grupo STP. Uma hora depois, os grupos DAN + CTM e DAN receberam 10mg/kg de DAN. Após sete dias os grupos CTM e DAN + CTM receberam 1x106 células, por via intravenosa. Testes comportamentais foram realizados para avaliar a recuperação funcional durante 28 dias. Os animais traumatizados apresentaram paraplegia. Houve melhora funcional significativa nos grupos tratados com CTM, DAN ou associação DAN + CTM em comparação ao grupo TP (p<0,05). Conclui-se que o DAN e as CTM para tratamento de TEA em ratos apresentam efeitos neuroprotetores e promovem melhora neurológica funcional.(AU)

This study aimed to evaluate the effects of dantrolene (DAN) and mesenchymal stem cells (MSCs) in acute spinal cord injury (SCI). Sixty Wistar rats were divided into groups MSCs, MSCs + DAN, DAN, trauma and placebo (TP) and no trauma and placebo (STP). Laminectomy was performed at T12 level in all animals, followed by a weight-drop model of SCI, except for the STP group. An hour later, the MSCs + DAN and DAN groups received 10mg/kg of DAN. After seven days, the MSCs and MSCs + DAN groups received 1x106 cells intravenously. Behavioral tests were performed to assess functional recovery for 28 days. Traumatized animals showed paraplegia. There was a significant improvement in groups MSCs, DAN and MSCs + DAN compared to TP (p<0.05). It was concluded that DAN and MSCs for the treatment of SCI in rats have neuroprotection effect and promote functional neurological improvement.(AU)

Omega-conotoxin MVIIC attenuates neuronal apoptosis in vitro and improves significant recovery after spinal cord injury in vivo in rats.

Excessive accumulation of intracellular calcium is the most critical step after spinal cord injury (SCI). Reducing the calcium influx should result in a better recovery from SCI. Calcium channel blockers have been shown a great potential in reducing brain and spinal cord injury. In this study, we first tested the neuroprotective effect of MVIIC on slices of spinal cord subjected to ischemia evaluating cell death and caspase-3 activation. Thereafter, we evaluated the efficacy of MVIIC in ameliorating damage following SCI in rats, for the first time in vivo. The spinal cord slices subjected a pretreatment with MVIIC showed a cell protection with a reduction of dead cells in 24.34% and of caspase-3-specific protease activation. In the in vivo experiment, Wistar rats were subjected to extradural compression of the spinal cord at the T12 vertebral level using a weigh of 70 g/cm, following intralesional treatment with either placebo or MVIIC in different doses (15, 30 and 60 pmol) five minutes after injury. Behavioral testing of hindlimb function was done using the Basso Beattie Bresnahan locomotor rating scale, and revealed significant recovery with 15 pmol (G15) compared to other trauma groups. Also, histological bladder structural revealed significant outcome in G15, with no morphological alterations, and anti-NeuN and TUNEL staining showed that G15 provided neuron preservation and indicated that this group had fewer neuron cell death, similar to sham. These results showed the neuroprotective effects of MVIIC in in vitro and in vivo model of SCI with neuronal integrity, bladder and behavioral improvements.